Man Friday
It's approximately 45 miles from LHR to LGW, so your driver must have AVERAGED around 60 mph. On the M25 that's pretty good going, even in the middle of the night.
dufc will be making the fourney around 9:00 a.m. - not exactly peak rush-hour but still heavy traffic. I would be surprised if his driver even reaches 60mph, let alone averages it!